The present invention relates to surgical guidance systems.
When performing minimally invasive percutaneous spinal surgery on a prone lying patient, such as when accessing the patient""s intervertebral area for the insertion of intervertebral inserts or the performing of a discectomy, the various necessary surgical tools and/or inserts should preferably access the patient""s spine in a posterolateral approach which is co-planar to the intervertebral plane passing between two selected adjacent vertebrae. Maintaining accurate positioning and guidance of surgical tools in this intervertebral plane has proven quite difficult to achieve in practice. Such positioning difficulties are further complicated by the fact that the intervertebral plane passing between any two adjacent vertebrae will be unique to that pair of adjacent vertebrae due to natural lordotic spinal curvature, sagittal plane variances as well as coronal plane variances.
The present invention provides a guidance platform for positioning one or more surgical instruments in an intervertebral plane which passes between two adjacent vertebrae in the patient""s spine such that the surgical instrument(s) can be held at a preferred angle while advanced in a percutaneous cannulated approach towards the patient""s intervertebral space.
An advantage of the present invention is that it can be used to support operating cannulae in the preferred intervertebral plane passing between any two selected vertebrae such that various surgical instruments and/or intervertebral inserts can be passed through the cannulae and into the patient""s intervertebral space in a preferred posterolateral approach.
Preferably, the present invention is used to position two cannulae, with each approaching the patient""s intervertebral space posterolaterally from the same or opposite sides. However, the positioning of only one cannula co-planar with the selected intervertebral plane is also contemplated. When separately positioning two operating cannulae, another advantage of the present invention is that it enables the simultaneous positioning of first and second surgical instruments with respect to one another and with respect to the patient""s spine such that each surgical instrument can be advanced into the patient from opposite posterolateral angles of approach.